During the height of the 2009 financial crisis , when there was a real and present danger of banks seizing up due to a lack of liquidity , the then-British Prime Minister Gordon Brown altered the geopolitical architecture .

Brown moved with a sense of urgency to formalize the Group of 20 nations .

The strategy was sound . He wanted to bring countries representing 80 % of GDP under one umbrella , bridge the gap between the developed and the developing world and , most importantly , tap the $ 4 trillion of surplus funds that still exist within the BRICS economies .

In the context of a financial crisis , the strategy worked . Four years later , however , geopolitics is trumping economics . The G20 has become an unwieldy group of countries with different priorities , and without political backing from Washington .

According to Brown , who I interviewed earlier this year , America `` should actually be more alert to the possibilities of international cooperation in both trade and agreements for growth . ''

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A global trade agreement , the much-talked about pivot to Asia , and even serious concerns around capital flight out of emerging markets and their currencies will be overshadowed at this G20 . Syria will be top of the agenda when the leaders convene in Russia 's western outpost of St. Petersburg .

Focus is on the tensions between host Vladimir Putin and his U.S. counterpart Barack Obama . Their verbal jousting could further divide the G20 , strategists suggest . The BRICS are , as a rule , not in favor of the military intervention being trumpeted by Washington and Paris .

`` Business has taken a back seat and it should move to the front seat , '' Mustafa Abdel-Wadood , chairman of the executive committee at the private equity group Abraaj told me . `` Politics tops the agenda . ''

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The business agenda is headed by the near-panic reaction to a planned tapering of bond purchases by the U.S. Federal Reserve . Since Federal Reserve Chairman Ben Bernanke uttered word of that change in strategy back in May , money has been flooding out of emerging markets .

Ahead of this week 's summit senior Chinese finance officials went out of their way to suggest , during a news conference in Beijing , the Federal Reserve should be more cautious with its approach .

China 's Vice Finance Minister Zhu Guangyao welcomed signs of the U.S. recovery but said Washington `` must consider the spill-over effect of its monetary policy , especially the opportunity and rhythm of its exit from the ultra-loose monetary policy . ''

The end of easy money or loose monetary policy in the U.S. is exposing the cracks in the emerging markets , which rode a decade-long , powerful wave of commodity-driven growth .

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Without that export demand for grains , gold , palm oil , rubber , minerals and even manufactured goods , economies such as Brazil , India , South Africa , Turkey and Indonesia have seen their current account deficits balloon and their currencies plummet .

The India rupee is down more than 20 % this year , most of that loss in the past quarter alone , as the country posted the worst growth in four years . Brazil and Indonesia have seen their currencies tumble 10 % , requiring central banks to use currency reserves and in some cases interest rate hikes to stop the bleeding .

The tendency is for investors to make comparisons to the 1998/1999 Asian financial crisis , when those economies had wide current account deficits and a mountain of foreign currency government debt .

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`` Most of Asia learned a lesson , '' Marios Maratheftis , global head of macro research at Standard Chartered Bank told me . The bulk of emerging market debt is now issued in local currencies .

Maratheftis said the `` sudden stop '' of capital flows to the emerging markets will create problems for those with widening current account deficits , but that this should not develop into a crisis provided there is a greater coordination of policies .

He is not holding out great hope for the discussions in St. Petersburg . `` They talk global when they meet , '' he said of the G20 . `` But act local when they go home . ''

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The G20 is being held in St Petersburg , but focus will be on tensions between Vladimir Putin and Barack Obama

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Discussions are meant to be around economics , but will be overshadowed by Syria

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Emerging markets have been suffering as demand for commodities drop , and currencies have collapsed

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John Defterios writes the G20 has become an unwieldy group of countries with different priorities